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United States Patent |
5,639,009
|
Abe
|
June 17, 1997
|
Apparatus and method for mounting tape carrier package onto liquid
crystal display
Abstract
An LCD 1 is evacuated from the focus range of the camera 4 in a horizontal
direction, while a positioning object 18 on a TCP 17 is placed in the
focus range of the visual field of the camera 4 to obtain a dislocation of
the TCP 17 by monitoring the positioning object 18. The TCP 17 is then
lifted in a vertical direction keeping its horizontal position until it
goes out of the focus range of the camera 4. The LCD 1 is returned in the
horizontal direction so that a positioning object 2 on the LCD 1 comes
into the focus range of the camera 4. Then, a dislocation of the LCD 1 is
detected by monitoring the positioning object 2. A mutual positional
relation is corrected by shifting at least either the LCD 1 or the TCP 17
in the horizontal direction based on the detected dislocations of the
positioning objects 2 and 18. Finally, the TCP 17 is lowered keeping its
horizontal position, and mounted on the LCD 1.
Inventors:
|
Abe; Toshiki (Fukuoka, JP)
|
Assignee:
|
Matsushita Electric Industrial Co., Ltd. (Osaka, JP)
|
Appl. No.:
|
540826 |
Filed:
|
October 11, 1995 |
Foreign Application Priority Data
Current U.S. Class: |
228/102; 228/6.2; 228/105 |
Intern'l Class: |
B23K 037/04 |
Field of Search: |
228/102,105,6.2,9
|
References Cited
U.S. Patent Documents
5042709 | Aug., 1991 | Cina et al. | 228/105.
|
5119436 | Jun., 1992 | Holdgrafer | 228/105.
|
Primary Examiner: Ramsey; Kenneth J.
Attorney, Agent or Firm: Pollock, Vande Sande & Priddy
Claims
What is claimed is:
1. A method for mounting a tape carrier package onto a liquid crystal
display, wherein a first positioning object on said tape carrier package
and a second positioning object on said liquid crystal display are
monitored by a camera, and said tape carrier package is mounted onto said
liquid crystal display after correcting a positional dislocation between
said tape carrier package and said liquid crystal display, said method
comprising:
a first step of detecting a first positional data representing a position
of said tape carrier package based on a monitoring of said first
positioning object, said first positioning object of said tape carrier
package coming in a focus range of a visual field of the camera after a
liquid crystal display is removed out of the visual field of the camera in
a horizontal direction;
a second step of detecting a second positional data representing a position
of said liquid crystal display based on a monitoring of said second
positioning object, said liquid crystal display being shifted in the
horizontal direction in such a manner that said second positioning object
comes into the focus range of the visual field of the camera after said
tape carrier package is lifted upward in a vertical direction until the
tape carrier package goes out of the focus range of the camera;
a third step of comparing an actual mutual position with a predetermined
ideal position based on said first and second positional data, thereby
correcting a mutual positional relationship between said tape carrier
package and said liquid crystal display in the horizontal direction; and
a fourth step of mounting said tape carrier package onto said liquid
crystal display.
2. The mounting method defined by claim 1, wherein said liquid crystal
display is held by an X-Y table, and shifted in the horizontal direction
by said X-Y table.
3. The mounting method defined by claim 1, wherein said tape carrier
package is held by a Z-axis motor shiftable in the vertical direction.
4. The mounting method defined by claim 1, wherein said first positioning
object on said tape carrier package is a lead formed on said tape carrier
package.
5. The mounting method defined by claim 1, wherein said first positioning
object on said tape carrier package is a mark provided on said tape
carrier package.
6. The mounting method defined by claim 1, wherein said second positioning
object on said liquid crystal display is an electrode formed on said
liquid crystal display.
7. The mounting method defined by claim 1, wherein said second positioning
object on said liquid crystal display is a mark provided on said liquid
crystal display.
8. A method for mounting a tape carrier package onto a liquid crystal
display comprising steps of:
providing a first positioning object on a tape carrier package and a second
positioning object on a liquid crystal display;
evacuating a liquid crystal display out of a visual field of a camera in a
horizontal direction;
shifting said tape carrier package until said first positioning object
comes in a focus range of the visual field of said camera;
detecting a first positional data representing a position of said tape
carrier package based on a monitoring of said first positioning object;
lifting said tape carrier package upward in a vertical direction until the
tape carrier package goes out of the focus range of the camera;
shifting said liquid crystal display in the horizontal direction so that
said second positioning object comes into the focus range of the visual
field of the camera;
detecting a second positional data representing a position of said liquid
crystal display based on a monitoring of said second positioning object;
correcting a mutual positional relationship between said tape carrier
package and said liquid crystal display in the horizontal direction based
on said first and second positional data; and
lowering said tape carrier package downward so that the tape carrier
package is mounted onto said liquid crystal display.
9. The mounting method defined by claim 8, wherein said first positional
data and said second positional data are compared with predetermined ideal
data, for detecting a horizontal deviation between said tape carrier
package and said liquid crystal display.
10. The mounting method defined by claim 8, wherein said at least either
the tape carrier package or the liquid crystal display is shifted in the
horizontal direction to correct the mutual positional relationship.
11. An apparatus for mounting a tape carrier package onto a liquid crystal
display, comprising:
a camera for taking images of a first positioning object on a tape carrier
package and a second positioning object on a liquid crystal display;
first shifting means for removing a liquid crystal display out of a visual
field of said camera in a horizontal direction;
second shifting means for shifting said tape carrier package until said
first positioning object comes in a focus range of the visual field of
said camera;
dislocation detecting means for detecting a first horizontal dislocation of
said first positioning object on said tape carrier package based on the
image of said first positioning object taken by said camera;
said second shifting means lifting said tape carrier package upward in a
vertical direction so that the tape carrier package goes out of the focus
range of the camera;
said first shifting means shifting said liquid crystal display in the
horizontal direction so that said second positioning object comes into the
focus range of the visual field of the camera;
said dislocation detecting means detecting a second horizontal dislocation
of said second positioning object on said liquid crystal display based on
the image of said second positioning object taken by said camera;
correcting means for correcting a mutual positional relationship between
said tape carrier package and said liquid crystal display in the
horizontal direction, by comparing said first and second horizontal
dislocations with predetermined ideal data; and
said second shifting means lowering said tape carrier package downward so
that the tape carrier package is mounted onto said liquid crystal display.
12. The mounting apparatus defined by said claim 11, wherein said first
shifting means is an X-Y table which supports said liquid crystal display
and is shiftable in the horizontal direction.
13. The mounting apparatus defined by claim 11, wherein said second
shifting means is a Z-axis motor which holds said tape carrier package and
is shiftable in the vertical direction.
14. The mounting apparatus defined by claim 11, wherein said correcting
means corrects the mutual positional relationship between said tape
carrier package and said liquid crystal display by shifting said first
shifting means in the horizontal direction.
15. An apparatus for mounting a tape carrier package onto a liquid crystal
display, wherein a horizontal dislocation between a first positioning
object on said tape carrier package and a second positioning object on
said liquid crystal display is checked and corrected before said tape
carrier package is mounted onto said liquid crystal display, said
apparatus comprising:
a camera having an optical axis extending upward along a mirror cylinder
connected to an upper face thereof;
a light source supplying light into said mirror cylinder via an optical
fiber, said light being emitted upward through said mirror cylinder and
used to monitor said first positioning object on said tape carrier package
and said second positioning object on said liquid crystal display;
an X-Y table for shifting said liquid crystal display along a horizontal
plane;
a Z-axis motor for shifting said tape carrier package in a vertical
direction;
an X-Y table drive for actuating said X-Y motor;
a Z-axis motor drive for actuating said Z-axis motor;
a dislocation detector for detecting said horizontal dislocation between
said first positioning object on said tape carrier package and said second
positioning object on said liquid crystal display; and
a controller for controlling said X-Y table drive and said Z-axis drive so
as to alternately bring said first and second positioning objects within a
focus range of said camera to detect each horizontal dislocation of said
first and second positioning objects, and adjusting a mutual positional
relationship between said tape carrier package and said liquid crystal
display based on the horizontal dislocation detected though said
dislocation detector before mounting said tape carrier package onto said
liquid crystal display.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to an apparatus and a method for mounting a tape
carrier package onto a liquid crystal display.
2. Prior Art
Before mounting a TCP (Tape Carrier Package) onto an LCD (liquid crystal
display), the positional relationship between the TCP and LCD is monitored
by a camera. And, if any positional dislocation is found between them, it
is necessary to eliminate such a dislocation. In general, the LCD and TCP
are provided with numerous thin electrodes and leads arrayed along the
sides thereof at very small pitches. The number of such electrodes and
leads will range from several tens to several hundreds. Thus, the mounting
of these LCD and TCP requires an extremely high accuracy in X and Y
directions.
As a method for monitoring the mutual positional relation between a TCP and
an LCD, there are known the following two methods.
A first method uses a camera whose visual field is stationarily fixed for
assuring accuracy in the recognition of these components. The LCD and the
TCP are supported movable in the X-Y direction (i.e. along a horizontal
plane). Then, the LCD and the TCP come in the visual field of the camera
but they are not overlapped. Under this condition, a mutual positional
dislocation is obtained through image analysis. Thereafter, both are
shifted to correct the mutual relation. Then, the mounting operation is
performed by overlapping the TCP onto the LCD.
A second method is carried out in the following manner. First, a TCP and an
LCD are overlap each other with a very small gap, so that the mounting
operation is soon accomplished by lowering the TCP onto the LCD by a very
small distance. This overlapped condition is monitored by a camera to
detect a dislocation between the TCP and the LCD.
However, it is usual that anisotropic conductive tapes are attached on
electrodes of the LCD to adhesively bond the electrodes to the leads of
the TCP. Thus, these anisotropic conductive tapes and the LCD itself may
become obstacles when the leads of the LCD are monitored by the camera
according to the above first and second methods. Thus, there is the
possibility that these first and second methods may fail to obtain a clear
image of the TCP, and therefore the detected position of the TCP may be
inaccurate, resulting in deterioration of accuracy in the mounting
operation. If the obtained image is unclear, the image analysis will
encounter with errors so frequently that the mounting operation of the TCP
is substantially stopped or suspended.
SUMMARY OF THE INVENTION
Accordingly, in view of above-described problems encountered in the prior
art, a principal object of the present invention is to provide a method
and an apparatus for assuring an excellent accuracy in the mounting
operation of a tape carrier package onto a liquid crystal display.
In order to accomplish this and other related objects, a first aspect of
the present invention provides a method for mounting a tape carrier
package onto a liquid crystal display, wherein a first positioning object
on the tape carrier package and a second positioning object on the liquid
crystal display are monitored by a camera, and the tape carrier package is
mounted onto the liquid crystal display after correcting a positional
relationship between the tape carrier package and the liquid crystal
display. The method comprises: a first step of detecting a first
positional data representing a position of the tape carrier package based
on a monitoring of the first positioning object, the first positioning
object of the tape carrier package coming in a focus range of a visual
field of the camera after a liquid crystal display is removed out of the
visual field of the camera in a horizontal direction; a second step of
detecting a second positional data representing a position of the liquid
crystal display based on a monitoring of the second positioning object,
the liquid crystal display being shifted in the horizontal direction in
such a manner that the second positioning object comes into the focus
range of the visual field of the camera after the tape carrier package is
lifted upward in a vertical direction until the tape carrier package goes
out of the focus range of the camera; a third step of comparing an actual
mutual position with a predetermined ideal position based on the first and
second positional data, thereby correcting a mutual positional
relationship between the tape carrier package and the liquid crystal
display in the horizontal direction; and a fourth step of mounting the
tape carrier package onto the liquid crystal display.
In the above first aspect mounting method, it is desirable that the liquid
crystal display is held by an X-Y table and shifted in the horizontal
direction by the X-Y table, and the tape carrier package is held by a
Z-axis motor shiftable in the vertical direction. The first positioning
object on the tape carrier package is a lead or a mark provided on the
tape carrier package. The second positioning object on the liquid crystal
display is an electrode or a mark provided on the liquid crystal display.
A second aspect of the present invention provides a method for mounting a
tape carrier package onto a liquid crystal display comprising steps of:
providing a first positioning object on a tape carrier package and a
second positioning object on a liquid crystal display; evacuating a liquid
crystal display out of a visual field of a camera in a horizontal
direction; shifting the tape carrier package until the first positioning
object comes in a focus range of the visual field of the camera; detecting
a first positional data representing a position of the tape carrier
package based on a monitoring of the first positioning object; lifting the
tape carrier package upward in a vertical direction until the tape carrier
package goes out of the focus range of the camera; shifting the liquid
crystal display in the horizontal direction so that the second positioning
object comes into the focus range of the visual field of the camera;
detecting a second positional data representing a position of the liquid
crystal display based on a monitoring of the second positioning object;
correcting a mutual positional relationship between the tape carrier
package and the liquid crystal display in the horizontal direction based
on the first and second positional data; and lowering the tape carrier
package downward so that the tape carrier package is mounted onto the
liquid crystal display.
In the above second aspect mounting method, it is desirable that the first
positional data and the second positional data are compared with
predetermined ideal data, for detecting a horizontal deviation between the
tape carrier package and the liquid crystal display. And, at least either
the tape carrier package or the liquid crystal display is shifted in the
horizontal direction to correct the mutual positional relationship.
Furthermore, a third aspect of the present invention provides an apparatus
for mounting a tape carrier package onto a liquid crystal display,
comprising: a camera for taking images of a first positioning object on a
tape carrier package and a second positioning object on a liquid crystal
display; first shifting means for removing a liquid crystal display out of
a visual field of the camera in a horizontal direction; second shifting
means for shifting the tape carrier package until the first positioning
object comes in a focus range of the visual field of the camera;
dislocation detecting means for detecting a first horizontal dislocation
of the first positioning object on the tape carrier package based on the
image of the first positioning object taken by the camera; the second
shifting means lifting the tape carrier package upward in a vertical
direction so that the tape carrier package goes out of the focus range of
the camera; the first shifting means shifting the liquid crystal display
in the horizontal direction so that the second positioning object comes
into the focus range of the visual field of the camera; the dislocation
detecting means detecting a second horizontal dislocation of the second
positioning object on the liquid crystal display based on the image of the
second positioning object taken by the camera; correcting means for
correcting a mutual positional relationship between the tape carrier
package and the liquid crystal display in the horizontal direction, by
comparing the first and second horizontal dislocations with predetermined
ideal data; and the second shifting means lowering the tape carrier
package downward so that the tape carrier package is mounted onto the
liquid crystal display.
In the third aspect mounting apparatus, it is desirable that the first
shifting means is an X-Y table which supports the liquid crystal display
and is shiftable in the horizontal direction, and the second shifting
means is a Z-axis motor which holds the tape carrier package and is
shiftable in the vertical direction. And, the correcting means corrects
the mutual positional relationship between the tape carrier package and
the liquid crystal display by shifting the first shifting means in the
horizontal direction.
Moreover, a fourth aspect of the present invention provides an apparatus
for mounting a tape carrier package onto a liquid crystal display, wherein
a horizontal dislocation between a first positioning object on the tape
carrier package and a second positioning object on the liquid crystal
display is checked and corrected before the tape carrier package is
mounted onto the liquid crystal display, the apparatus comprising: a
camera having an optical axis extending upward along a mirror cylinder
connected to an upper face thereof; a light source supplying light into
the mirror cylinder via an optical fiber, the light being emitted upward
through the mirror cylinder and used to monitor the first positioning
object on the tape carrier package and the second positioning object on
the liquid crystal display; an X-Y table for shifting the liquid crystal
display along a horizontal plane; a Z-axis motor for shifting the tape
carrier package in a vertical direction; an X-Y table drive for actuating
the X-Y motor; a Z-axis motor drive for actuating the Z-axis motor; a
dislocation detector for detecting the horizontal dislocation between the
first positioning object on the tape carrier package and the second
positioning object on the liquid crystal display; and a controller for
controlling the X-Y table drive and the Z-axis drive so as to alternately
bring the first and second positioning objects within a focus range of the
camera to detect each horizontal dislocation of the first and second
positioning objects, and adjusting a mutual positional relationship
between the tape carrier package and the liquid crystal display based on
the horizontal dislocation detected though the dislocation detector before
mounting the tape carrier package onto the liquid crystal display.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other objects, features and advantages of the present
invention will become more apparent from the following detailed
description which is to be read in conjunction with the accompanying
drawings, in which:
FIG. 1 is a schematic view showing a tape carrier package mounting system
in accordance with one embodiment of the present invention;
FIG. 2 is a view illustrating an operation of the tape carrier package
mounting system in accordance with the embodiment of the present
invention;
FIG. 3 is a view illustrating an operation of the tape carrier package
mounting system in accordance with the embodiment of the present
invention;
FIG. 4 is a flow chart showing an operation of the TCP mounting system in
accordance with the embodiment of the present invention; and
FIG. 5 is a perspective view showing manufacturing processes of a tape
carrier package.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
A preferred embodiment of the present invention will be explained in
greater detail hereinafter, with reference to the accompanying drawings.
Identical parts are denoted by identical reference numeral throughout
views.
FIG. 1 is a schematic view showing a tape carrier package mounting system
in accordance with one embodiment of the present invention.
In FIG. 1, reference numeral 1 represents a liquid crystal display (i.e.
LCD). A positioning object 2, such as an electrode or a mark, is provided
on the upper surface of the LCD 1. Reference numeral 3 represents an X-Y
table which mounts the LCD 1 on the upper face thereof, and shifts the LCD
1 along a horizontal plane, i.e. both in X and Y directions. Reference
numeral 4 represents a camera, and reference numeral 5 represents a mirror
cylinder connected to the camera 4 and extending upward from the upper
face of the camera 4. Reference numeral 6 represents a light source, and
reference numeral 7 represents an optical fiber supplying light emitted
from the light source 6 into an inside space of the mirror cylinder 5. As
shown in FIG. 2, the mirror cylinder 5 has an inside hollow space with a
half mirror 5a so that the light supplied from the light source 6 via the
optical fiber 7 is reflected at the half mirror 5a toward the direction
normal to the incident direction thereof and then travels upward along the
axis of the elongated cylindrical body of the mirror cylinder 5. The light
emitted along the axial direction of the mirror cylinder 5 is used to scan
or monitor the positioning object 2 on the LCD 1 by the camera 4. Namely,
the mirror cylinder 5 is placed along the optical axis of the camera 4.
Reference numeral 8 represents another optical fiber supplying light from
the light source 6 to a lighting portion 9. The light supplied from the
lighting portion 9 via the optical fiber 8 is used to scan or monitor a
positioning object 18, such as a lead or a positioning mark, provided on a
tape carrier package 17.
Details of the tape carrier package 17 will be explained hereinafter with
reference to FIG. 5. The tape carrier package (i.e. TCP) is an electronic
component manufactured by the following Tape Automated Bonding method.
First of all, a conductive metallic film 100 (e.g. copper film) is attached
or bonded on the surface of a carrier tape 101 made of insulating resin
such as polyimide. Then, numerous leads 102 are formed by etching the
metallic film 100. One end of each lead 102 overhangs in a device hole 103
opened on the carrier tape 101. Subsequently, a semiconductor chip 104 is
mounted in the device hole 103 in such a manner that the electrodes of the
semiconductor chip 104 are bonded to the distal ends of overhanging leads
102. For protecting the bonding portions between the leads 102 and
corresponding electrodes of the semiconductor chip 104, they are covered
by resin coating 105. Thereafter, a rectangular piece including the bonded
semiconductor chip 104 therein is separated or taken out by cutting the
carrier tape 101 along a cutting line 106 using dies (not shown). Thus, an
electronic component called as tape carrier package is obtained.
Returning to FIG. 1, reference numeral 10 represents a shift table, and
reference numeral 11 represents a vertically extending box fixed on the
front face of the shift table 10. Reference numeral 12 represents a
bracket supported and shiftable along the vertically extending front face
of the box 11. A vertically extending feed screw 13 is supported in the
box 11 so as to be rotatable about its axis. A Z-axis motor 14 with an
output shaft protruding downward is fixed on the upper face of the box 11.
With actuation of the Z-axis motor 14, the feed screw 13 is rotated.
Reference numeral 15 represents a feed nut fixed on the rear face of the
bracket 12 and engaged with the feed screw 13. A nozzle 16, extending
downward from the lower face of the bracket 12, has a lower surface for
absorbing the TCP 17 and holding it horizontally. Accordingly, after the
shift table 10 is stopped, the Z-axis motor 14 is driven so as to rotate
the feed screw 13, thereby elevating and lowering the TCP 17 in the
vertical direction without changing the X-Y position thereof.
Reference numeral 20 represents a controller, constituted by a CPU or the
like, for controlling the TCP mounting system. Reference numeral El
represents an X-Y table drive for actuating the X-Y table. Reference
numeral 22 represents a Z-axis motor drive for driving the Z-axis motor
14. Reference numeral 23 represents a dislocation detector for detecting
dislocation (or deviation) amounts of the positioning object 2 on the LCD
1 and the positioning object 18 on the TCP 17 by processing the images
obtained by the camera 4 based on pattern matching or the like.
An operation of the TCP mounting system as constituted above will be next
explained with reference to the views of FIGS. 2 and 3 and the flow chart
shown in FIG. 4.
First, in step S1, the controller 20 sends a drive signal to the X-Y table
drive 21 to drive the X-Y table 3 in a horizontal direction. Then, in step
S2, it is checked as to whether or not the LCD 1 goes out of the visual
field of the camera 4. If the answer of step S2 is "NO", the controller 20
repeats the step S1 until an "YES" answer is obtained in the step S2. On
the other hand, if the answer of step S2 is "YES", the controller 20
proceeds to the next step S3 wherein the shift table 10 is moved in the
horizontal direction. Then, in step S4, it is judged whether or not the
positioning object 18 of the TCP 17 is located above the camera 4. Namely,
the TCP 17 held by the nozzle 16 is shifted in the horizontal direction
together with the shift table 10, until the positioning object 18 provided
on the lower surface of the TCP 17 is positioned just above the mirror
cylinder 5, thereby locating the positioning object 18 of the TCP 17
within a focus range "A" (shown in FIG. 3) of the visual field of the
camera 4.
If the answer of step S4 is "NO", the controller 20 repeats the step S3
until the positioning object 18 of the TCP 17 is completely located within
the focus range "A" of the visual field of the camera 4. On the other
hand, if the answer of step S4 is "YES", the controller 20 proceeds to the
next step S5. Once the positioning of the shift table 10 is completed
through the above steps S3 and S4, the position of the shift table 10 is
no longer changed unless the mounting operation of the TCP 17 (later
described) is completed.
Next, in the step S5, the controller 20 turns on the light source 6 to emit
light upward obliquely (in a direction of an arrow "N1") via the optical
fiber 8 and the lighting portion 9. Thus emitted light is used to light up
the positioning object 18 of the TCP 17. The light is then reflected
toward multiple directions from the rough surface of the positioning
object 18 of the TCP 17, with some light entering into the mirror cylinder
5 along an arrow N2. The reflected light introduced into the mirror
cylinder 5 then penetrates the half mirror 5a and enters into the camera
4. In step S6, the camera 4 outputs an image of the positioning object 18
of the TCP 17 based on the reflected light, and the image is then analyzed
to obtain positional data representing the positioning object 18. The
dislocation detector 23 obtains a dislocation (or deviation) of the
positioning object 18 of the TCP 17 based on a comparison between the
actually detected position and a predetermined ideal position. Thus,
obtained dislocation data is sent from the dislocation detector 23 to the
controller 20. (Step S7)
Next, in step S8, the controller 20 sends a drive signal to the Z-axis
motor drive 22 to actuate the Z-axis motor 14 in a vertical direction,
thereby lifting the TCP 17 upward as shown by an arrow N3 in FIG. 3. In
the next step S9, it is checked whether the TCP 17 goes out of the focus
range "A" of the camera 4. If the answer of step S9 is "NO", the
controller 20 repeats the step S8 until "YES" answer is obtained. 0n the
other hand, if the answer of step S9 is "YES", the controller 20 proceeds
to step S10. Namely, the TCP 17 needs to be lifted upward until it
completely goes out of the focus range "A" of the visual field of the
camera 4.
Then, in step S10, the controller 20 sends a drive signal again to the X-Y
table drive 21 to drive the X-Y table 3 back in the horizontal direction
as shown by an arrow N4. Then, in step S11, it is checked as to whether or
not the LCD 1 returns within the focus range "A" of the camera 4. If the
answer of step S11 is "NO", the controller 20 repeats the step S10 until a
"YES" answer is obtained in the step S11. On the other hand, if the answer
of step S11 is "YES", the controller 20 proceeds to the next step S12
wherein the positioning object 2 of the LCD 1 is lighted up by the light
supplied from the light source 6 via the optical fiber 7 and the half
mirror 5a and emitted in a direction of an arrow N5. The light is then
reflected from the surface of the positioning object 2 and returns along a
direction of an arrow N6. The reflected light introduced into the mirror
cylinder 5 then penetrates the half mirror 5a and enters into the camera
4.
In step S13, the camera 4 outputs an image of the positioning object 2 of
LCD 1 based on the reflected light, and the image is then analyzed to
obtain positional data representing the positioning object 2 of LCD 1. The
dislocation detector 23 obtains a dislocation (or deviation) of the
positioning object 2 of the LCD 1 based on a comparison between the
actually detected position and a predetermined ideal position. Thus,
obtained dislocation data is sent from the dislocation detector 23 to the
controller 20. (Step S14)
In the monitoring operation of the positioning object 2 on the LCD 1, the
TCP 17 is located on an optical axis (i.e. visual field) of the camera 4.
However, the TCP 17 does not give an adverse effect on this monitoring
operation, because the TCP 17 is raised so far from the focus range "A" of
the camera 4. Thus, it is possible to obtain a noiseless image of the LCD
1.
Next, in step S15, it is judged as to whether or not the positional
correction is required in the relation between the LCD 1 and the TCP 17,
based on the dislocation values obtained in the steps S7 and S14. In other
words, the actual mutual position between the LCD 1 and the TCP 17 in the
horizontal direction is compared with a predetermined ideal position in
the step S15. More specifically, if any dislocation (or deviation) is
detected in the steps S7 and S14, the controller 20 adjusts the mutual
position between the LCD 1 and the TCP 17 to realize a predesignated ideal
mutual relational relationship.
If the answer of step 15 is "NO", the controller 20 proceeds to step S18.
On the other hand, if the answer of step 15 is "YES", the controller 20
proceeds to step 16 to drive the X-Y table 3 in the horizontal (X-Y)
direction, thereby adjusting the mutual position between the LCD 1 and the
TCP 17. Subsequently, in step S17, it is judged whether or not the
adjustment of the mutual position between the LCD 1 and the TCP 17 is
completed. If the answer of step S17 is "NO", the controller 20 repeats
the step S16 until a "YES" answer is obtained in the step S17. On the
other hand, if the answer of step S17 is "YES", the controller 20 proceeds
to the next step S18 wherein the controller 20 sends a drive signal to the
Z-axis motor drive 22 to actuate the Z-axis motor 14 to lower the TCP 17
downward. Then, in step S19, it is checked whether or not the TCP 17 is
mounted on the LCD 1. If the answer of step S19 is "NO", the controller 20
repeats the step S18 until a "YES" answer is obtained. On the contrary,
when the answer of step S18 is "YES", the controller 20 ends the mounting
operation.
Although the above embodiment is explained based on the LCD 1 shiftable in
the horizontal direction, it is, however, possible to move the TCP 17 in
the horizontal direction.
As this invention may be embodied in several forms without departing from
the spirit of essential characteristics thereof, the present embodiment as
described is therefore intended to be only illustrative and not
restrictive, since the scope of the invention is defined by the appended
claims rather than by the description preceding them, and all changes that
fall within metes and bounds of the claims, or equivalents of such metes
and bounds, are therefore intended to be embraced by the claims.
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